The commenting system on files and images in the database has been changed. You should no longer receive a pop-up form to fill-in but instead a form will become available on the same page for you to submit. Upon submitting your comments they should become visible without the need to refresh the page yourself.
In a similar vein the "Vote for this file" and "Track this file" links on all sites have now been ajax'ified and should now pop-up in their own little notification windows.
These changes were tested on IE, Fire Fox and Chrome in various resolutions. If you come across a problem first press Ctrl + F5 in your browser; this will refresh all the content on the page from scratch rather than using your browser cache. If the problem persists please provide feedback containing the problem and how to replicate it, what browser you're using, what version of the browser you are using and at what screen resolution you're running at.